Hambantota, Sri Lanka: Australia captain Michael Clarke has urged his team to raise their game in the remaining two one-day internationals against Sri Lanka to clinch the five-match series.

Australia were let down by the batsmen during the third one-dayer on Tuesday as they suffered a 78-run defeat, their first in six matches under Clarke who replaced Ricky Ponting as captain after the World Cup.

Sri Lanka rode on opener Upul Tharanga's 111 to post a challenging 286-9 in the must-win match before dismissing Australia for 208, with paceman Lasith Malinga (5-28) doing the most damage.

"We have some work to do over the next few days because playing against Sri Lanka, especially in their home conditions, you have to be at your best to beat them," Clarke said after the day-night match.

Australia, currently ahead 2-1 in the five-match series, will play the last two games in Colombo on Saturday and Monday.

Clarke (46) and Michael Hussey (63) alone defied Sri Lanka's attack on Tuesday as they added 71 for the fourth wicket, but the remaining batsmen faltered against pace.